Color

#0051ff

#0051ff
hex#0051ff
rgbrgb(0, 81, 255)
hslhsl(221, 100%, 50%)
oklchoklch(0.527 0.264 262.9)
Closest name: C64 Blue (#003aff)Relative luminance 0.131

Colors that go with #0051ff

Charcoal, Crimson and Amber lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#ffae00

#00d0ff · #2f00ff

#ff0051 · #51ff00

Split-complementary

Open in tool →

#ff2f00 · #d0ff00

#ff00d0 · #ffae00 · #00ff2f

Contrast

#0051ff as textRatioAAAA largeAAAFix
Aaon white
5.8:1passpassfail
  • AAA: use #0047e0 as the text (7.05:1)
Aaon black
3.62:1failpassfail
  • AA: use #2469ff as the text (4.54:1)
  • AAA: use #6193ff as the text (7.13:1)
  • AA: or shift the background to #e3e3e3 (4.52:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0051ff as the background.

Brands using this color

Fonts for this mood

#0051ff reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0051ff
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #0051ff and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0051ff-9ca4c4-df6b4e-211f2d-e9eff1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md